The Biomarker Analytical Research Core (BARC) provides cost effective and efficient analyses, methodologies to promote the diabetes research efforts of the Einstein-Mount Sinai Diabetes Research Center (ES-DRC) spanning the translational spectrum. The BARC integrates high quality sample extraction and processing, computerized sample tracking using a laboratory information management system (LIMS), high-throughput robotics for hormone assays and metabolite measurements, gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) measurement of metabolites, steroids and protein hormones. Specific areas of expertise include high-throughput parallel assay measurements, stable isotope measurements of steroids, C-peptide and C-peptide kinetics, and insulin biosynthesis measurements in human subjects. The BARC also coordinates and enhances measures of stable isotope glucose, fatty acid, triglyceride and amino acid flux in humans and rodents with the flux/metabolomic measurements performed in the Stable Isotope & Metabolomics Core. To accomplish these goals, the BARC will: 1) provide high quality, validated immunoassays using high throughput semi-automated sample handling, parallel assay measurements from single thawed source samples (animal or human), and chain of custody data output; 2 provide specialized measurements (gold standard or reference methods) from human biofluids of physiological carbohydrates, steroid hormones, and C-peptide by GC/MS or LC/MS quantification; 3) provide measurements of radioactive metabolites labeled with 3H and 14C using high-throughput gamma counting suitable for animal and human physiologic turnover studies and radioimmunoassay; 4) provide specialized equipment for high efficiency extraction while preserving analyte integrity of RNA, DNA and proteins for molecular biology, proteomic and biomarker analyses; 5) provide guidance for proper study design for the measurement in human study subjects of hepatic glucose production, whole body glucose disposal, fatty acid, triglyceride and amino acid turnover, hepatic blood flow, insulin secretion and insulin biosynthesis; and 6) coordinate these efforts with other ES- DRC and Institutional Core facilities at Einstein and Mount Sinai. All of these services are available to investigators new to diabetes research, as well as to investigators working on diabetes-related projects that can be enriched and extended by the use of the expertise and facilities of this Core.